
import java.util.Scanner;

public class Main {
    private static int n, m, ret;

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        n = scanner.nextInt();
        m = scanner.nextInt();
        ret = 0;
        f(0, 0);
        System.out.println(ret);
    }

    public static void f(int x, int y) {
        if (x > n || y > m) return;
        if (x == n && y == m) {
            ret++;
            return;
        }
        //向右走
        f(x, y + 1);
        //向下走
        f(x + 1, y);
    }
}
